/**
 * $Id: Bitmap.cpp 29 2010-08-03 08:48:43Z bearice $
 * Copyright (C) 2010 Bearice
**/
#include "stdafx.h"
#include "Bitmap.h"

void Bitmap_FreeBMPInfo(PBITMAPINFO info){
	LocalFree(info);
}

PBITMAPINFO Bitmap_CreateBMPInfo(LPBITMAP bmp) { 
   // BITMAP bmp; 
    PBITMAPINFO pbmi; 
    WORD    cClrBits; 

  /*  // Retrieve the bitmap color format, width, and height. 
    if (!GetObject(hBmp, sizeof(BITMAP), (LPSTR)&bmp)) 
        return NULL;
		*/
    // Convert the color format to a count of bits. 
    cClrBits = (WORD)(bmp->bmPlanes * bmp->bmBitsPixel); 
    if (cClrBits == 1) 
        cClrBits = 1; 
    else if (cClrBits <= 4) 
        cClrBits = 4; 
    else if (cClrBits <= 8) 
        cClrBits = 8; 
    else if (cClrBits <= 16) 
        cClrBits = 16; 
    else if (cClrBits <= 24) 
        cClrBits = 24; 
    else cClrBits = 32; 

    // Allocate memory for the BITMAPINFO structure. (This structure 
    // contains a BITMAPINFOHEADER structure and an array of RGBQUAD 
    // data structures.) 

     if (cClrBits != 24) 
         pbmi = (PBITMAPINFO) LocalAlloc(LPTR, 
                    sizeof(BITMAPINFOHEADER) + 
                    sizeof(RGBQUAD) * (1<< cClrBits)); 

     // There is no RGBQUAD array for the 24-bit-per-pixel format. 

     else 
         pbmi = (PBITMAPINFO) LocalAlloc(LPTR, 
                    sizeof(BITMAPINFOHEADER)); 

    // Initialize the fields in the BITMAPINFO structure. 

    pbmi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER); 
    pbmi->bmiHeader.biWidth = bmp->bmWidth; 
    pbmi->bmiHeader.biHeight = bmp->bmHeight; 
    pbmi->bmiHeader.biPlanes = bmp->bmPlanes; 
    pbmi->bmiHeader.biBitCount = bmp->bmBitsPixel; 
    if (cClrBits < 24) 
        pbmi->bmiHeader.biClrUsed = (1<<cClrBits); 

    // If the bitmap is not compressed, set the BI_RGB flag. 
    pbmi->bmiHeader.biCompression = BI_RGB; 

    // Compute the number of bytes in the array of color 
    // indices and store the result in biSizeImage. 
    // For Windows NT, the width must be DWORD aligned unless 
    // the bitmap is RLE compressed. This example shows this. 
    // For Windows 95/98/Me, the width must be WORD aligned unless the 
    // bitmap is RLE compressed.
    pbmi->bmiHeader.biSizeImage = ((pbmi->bmiHeader.biWidth * cClrBits +31) & ~31) /8
                                  * pbmi->bmiHeader.biHeight; 
    // Set biClrImportant to 0, indicating that all of the 
    // device colors are important. 
     pbmi->bmiHeader.biClrImportant = 0; 
     return pbmi; 
 } 

int Bitmap_GetBufferSize(PBITMAPINFO pbi){
	return 
		sizeof(BITMAPFILEHEADER) + 
		pbi->bmiHeader.biSize + 
		pbi->bmiHeader.biClrUsed * sizeof (RGBQUAD)+
		pbi->bmiHeader.biSizeImage;
}

int Bitmap_WriteBuffer(char* buffer, int buflen, PBITMAPINFO pbi, HBITMAP hBMP, HDC hDC) { 
    BITMAPFILEHEADER hdr;       // bitmap file-header 
    PBITMAPINFOHEADER pbih;     // bitmap info-header 
	if(Bitmap_GetBufferSize(pbi)>buflen)return 0;
	int w=0;
	pbih = &pbi->bmiHeader;
    hdr.bfType = 0x4d42;
    hdr.bfSize = (DWORD) (sizeof(BITMAPFILEHEADER) + pbih->biSize + pbih->biClrUsed*sizeof(RGBQUAD) + pbih->biSizeImage); 
    hdr.bfReserved1 = 0; 
    hdr.bfReserved2 = 0; 

    // Compute the offset to the array of color indices. 
    hdr.bfOffBits = (DWORD) sizeof(BITMAPFILEHEADER) + 
                    pbih->biSize + pbih->biClrUsed 
                    * sizeof (RGBQUAD); 

    memcpy(buffer,(LPVOID) &hdr, sizeof(BITMAPFILEHEADER));
	w += sizeof(BITMAPFILEHEADER);
    memcpy(buffer+w,(LPVOID) pbih, pbih->biSize + pbih->biClrUsed * sizeof (RGBQUAD));
	w += pbih->biSize + pbih->biClrUsed * sizeof (RGBQUAD);

	if (!GetDIBits(hDC, hBMP, 0, (WORD) pbih->biHeight, buffer+w, pbi, DIB_RGB_COLORS)) 
		return -1;
	w+=pbih->biSizeImage;
	return w;
}